Yamaha Corporation

Noro Masao

Masamitsu Hirano

A sound field expanding apparatus is formed from an L-channel sound field expanding circuit and an R-channel sound field expanding circuit that have substantially the same circuit structure. Left and right stereophonic input signals of two channels are input in the L-channel sound field expanding circuit and the R-channel sound field expanding circuit, respectively. The L-channel sound field expanding circuit and the R-channel sound field expanding circuit include a first amplitude/phase characteristic changing circuit and a second amplitude/phase characteristic changing circuit, respectively. The first amplitude/phase characteristic changing circuit and the second amplitude/phase characteristic changing circuit add specified amplitude/phase characteristics to the respective input signals to generate a specified sound field expanding effect. The first and second amplitude/phase characteristic changing circuits are formed on a single IC chip with switched capacitor filters, and have the same structure for both of the first and second amplitude/phase characteristic changing circuits.

Growing community of inventors

Shizuoka-ken, Japan

Noro Masao